1. Field Of The Invention
The invention relates to a shaped charge carrier assembly of the type used to perforate an oil or gas well. The invention particularly pertains to the construction of a strip type carrier providing an angular offset between adjacent charges, and to the construction of a carrier opening and associated shaped charge to provide for an interlocking engagement of the charge with the opening.
2. Description Of The Prior Art
Perforating guns commonly used in wire line service operations for perforating an oil or gas well typically include a carrier having a plurality of shaped charges attached thereto with a detonating cord assembled with the carrier and engaged with the shaped charges for detonating them. This assembly may be housed in a hollow cylindrical housing, or in some cases, the carrier assembly itself is lowered into the well without a protective housing. If a protective housing is not utilized, a dome-shaped cover may be placed over the forward face of the shaped charge to assure that an appropriate minimum standoff distance is maintained between the charge and the wellbore.
The prior art has included a number of strip type carriers wherein the carrier is constructed from sheet metal. Openings are formed through the sheet metal carrier, and the shaped charges are inserted through the openings and attached to the carrier with some form of lug type attachment means or a clip. Examples of such prior art devices are shown in U.S. Pat. No. 3,078,797 to Blair, U.S. Pat. No. 4,326,462 to Garcia et al., U.S. Pat. No. 3,048,101 to LeBourg, U.S. Pat. No. 3,094,930 to Blair and U.S. Pat. No. 2,756,677 to McCullough.
It is also known in the prior art to radially stagger adjacent charges so that an angle of, for example, 45.degree., 60.degree. or 90.degree. is provided between adjacent charges. Examples of such prior art devices include U.S. Pat. No. 2,756,677 to McCullough mentioned above, and U.S. Pat. No. 2,750,884 to Gaines.